Fruit load or fruit position alters response to temperature and subsequently cherry tomato quality

Abstract

Changes in fruit-source ratio during the growth and maturation of cherry tomato fruits were studied in combination with increased fruit temperature. Six treatments were compared: the presence or absence of local heating combined with different fruit origins (7P, fruit from trusses pruned to seven flowers; 14P, proximal fruits; 14D, distal fruits from trusses pruned to 14 flowers). 7P were less sensitive to heating whereas 14P and 14D showed greater reduction in water and dry matter (DM) content. Distal fruits had the lowest structural DM (sDM), which could be due to a lower fruit cell number. Heating further decreased the sDM, so that fruit sink size was the lowest for distal fruits subjected to heating. Under low competition (7P), heating had a beneficial effect on sugar and lycopene content, whereas acids, β-carotene and vitamin C content were reduced. Under high competition (14P, 14D), heating increased the ratio sDM-DM. This was mainly due to the reduced content of sugars and acids, but also to the reduced accumulation of secondary metabolites such as vitamin C, β-carotene and lycopene. This study underlines the interactions between fruit temperature and the fruit-source ratio and the consequences for fruit composition and nutritional quality.

Tomato quality is more dependent on temperature than on photosynthetically active radiation

“…7). This could be due to high fruit load at higher temperatures as suggested by Gautier et al 10 Increased fruit temperature leads to a higher transpirational flux, which in turn stimulates the translocation of nutrients to the fruit sink, thereby increasing sink strength. Increased day temperature can induce an increase in the Vit C content of tomatoes.…”

“…Although temperature is known to affect cell wall properties responsible for fruit texture, 20 its effect on tomato firmness is still not clear. For instance, Gautier et al 10 found no change in fruit firmness as a result of a 1.1…”

“…This is, at least partly, due to a variety of reasons: (i) parameters of tomato quality have often been related to mean climatic data over the entire season or growing cycle, being then only slightly indicative of the climatic conditions that actually occurred from anthesis to harvest; (ii) the source/sink balance has been reported to influence tomato quality; 8 and (iii) the response of tomato quality to environmental conditions is cultivardependent 9 and also depends on fruit position within the truss. 10 In particular, the relative importance of the influence of air temperature and photosynthetically active radiation (PAR) on tomato quality remains unclear, mainly owing to the difficulty in separating these two parameters inside greenhouses (in general, temperature is positively correlated with solar radiation in greenhouses). In particular, very little is known regarding the influence of air temperature on tomato quality under low levels of PAR.…”

Remarkable Reproducibility of Enzyme Activity Profiles in Tomato Fruits Grown under Contrasting Environments Provides a Roadmap for Studies of Fruit Metabolism

“…Finally, fruit load (Do et al, 2010) and fruit position also influence quality. Tomato fruits are known to compete within a truss (Gautier et al, 2005), and greenhouse tomato producers usually prune trusses to maximize fruit growth and quality. The position of the truss on the plant has also been found to influence various metabolites in the fruits (Bénard et al, 2009), including lycopene and b-carotene (Fanasca et al, 2007), as well as seed quality (Dias et al, 2006).…”

The Effect of Potassium Biofortification Over Yield and Nutritional Quality of Cherry Tomato Fruits

“…These results appear to agree with those of the present study at 24 and 29 WAT (Table 3) (Figs. 1 A and 2 A, 2B), as the decline in the lycopene content could be due to the oxidation of this compound to β-carotene; however, β-carotene degradation also intensifies from 35 to 40ºC (Rosales et al, 2006;Gautier et al, 2005).…”